It's not gambling that can build your character but it's important that you have a good and strong character if you are going to gamble, you cannot justify that you are gambling because you want to develop a good trait, it's like justifying why you are spending and losing a lot of money, I prefer to look at gambling as it is and that is to get entertain, and spending more money and time will lead you to lose money and time.
Are you going to recommend gambling to build character it's like heading them into a quicksand.